• The Journal of Engineering Geology
• /
• v.18 no.4
• /
• pp.555-566
• /
• 2008

Hydrogeochemical study in Samseung area (Boeun, Chungbuk) and waterrock interaction experiment using rock samples from the area were performed to elucidate the fluoride source in groundwater and explaining geochemical behavior of fluoride ion. Fluoride concentration of public water supply mostly using groundwater in Boeun area was significantly higher in South Korea. The maximum fluoride concentration of the study area was 3.9 mg/L, and 23% of samples exceeded the Korean Drinking Water Standard of fluoride (1.5 mg/L). The average concentration of fluoride was 1.0 mg/L and median was 0.5 mg/L. Because of high skewness (1.3), median value is more appropriate to represent fluoride level of this area. The relationships between fluoride ion and geochemical parameters ($Na^+$, $HCO_3$, pH, etc.) indicated that the degree of waterrock interaction was not significant. However, high fluoride samples were observed in $NaHCO_3$ type on Piper's diagram. The negative relationship between fluoride and $NO_3$ ion which might originate from surface contaminants was obvious. These results indicate that fluoride ion in groundwater is geogenic origin. The source of fluoride was proved by waterrock interaction batch test. Fluoride concentration increased up to 1.2 mg/L after 96 hours of reaction between water and biotite granite. However, the relationship between well depth and fluoride ion, and groundwater age and fluoride ion was not clear. This indicates that fluoride ion is not correlated with degree of waterrock interaction in this area but local heterogeneity of fluoriderich minerals in granite terrain. High fluoride concentration in Boeun area seems to be correlated with distribution of permeable structures in hard rocks such as lineaments and faults of this area. This entails that the deep bedrock groundwater discharges through the permeable structures and mixed with shallow groundwater.

• Applied Microscopy
• /
• v.15 no.2
• /
• pp.31-68
• /
• 1985

Authors are trying to unveil the ultrastructural organization of olfactory bulb, which has been summerized under light microscopic level or communicated only in some detail in different view point until now. For the critical point of view, since the phylogenetical approach will give the ultimate value in the correlative study between structural and functional bases (Brodal, 1969), the present study was carried out light and electron microscopic analyses of the structures of the neurons and synaptic organizations in olfactory bulbs from different animals in phylogenetical scale. We selected each one species from five animal classes: the house rabbit(Oryctolagus cuniculus var. domesticus [Gmelin]) from Mammalia, the domestic fowl (Gallus gallus domesticus Brisson) from Aves, the viper (Agkistrodon hylys [G.P. Pallas]) from Reptilia, a frog (Bombiana orientalis Boulenger) from Amphibia and the crussian carp (Carassius carassius [Linne]) from Pisces. For light microscopic study, samples were fixed in 10% formalin and paraffin sections were stained with hematoxylin-eosin. For the electron microscopic study, the tissues were fixed by perfusion through the heart or immersion with 1% paraform-aldehyde-glutaraldehyde mixture (phosphate buffer, pH 7.4), and final tissue block trimmed under dissecting microscope were osmicated (1% OsO4), they were embedded in Araldite or Epon 812, and ultrathin sections were made by LKB-V ultratome following the inspection of semi-thin sections stained with toluidine blue-borax solution. Ultra-thin sections contrasted with uranyl acetate and lead citrate were observed with JEM 100CX electron microscope. We have summerized our morphological analyses as follows: 1. The olfactory bulb of rabbit, viper and frog shows the eight layers of fila olfactoria, glomerular, external granular, external plexiform, mitral cell, internal plexiform, internal granular, medullary but domestic fowl shows the five layers of glomerular, fibrillar, mitral, granular and medullary and the three layers of fibrilla, glomerular and medullary in crussian carp. The sharpness of demarcation between the layers shows deferential tendency according to phylogenetical order. 2. Mitral cells of vertebrate have large triangular or oval shape with spherical nuclei which contain not so much chromatin. The cytoplasm contains numerous cell organelles, of which Nissl's bodies or granular endoplasmic reticula arranged as parallel strands. Development of granular endoplasmic reticula were declined as the phylogentical grade is going lower. 3. Tufted cells of all animal are mostly spindle or polygonal contour and contain oval nuclei which located in periphery of cytoplasm. The nuclei of rabbit, fowl, viper and frog has relatively space chromatin, but a nucleus of crussian carp contain irregularly aggregated chromatin in karyoplasm. Their cytoplasmic volume and cell organelle contents are in between those of mitral cell and granular cell. They contain moderate amount of mitochondria, granular endoplasmic reticula, a few Golgi complex, polysomes, lysosome, etc. 4. Granule of cells of all the vertebrate amimals studied exhibit similar features; cells and their dense nuclei show spherical or oval contour, and they have the thin rim of cytoplasm which contain only a few cell organelles. 5. In rabbit, the soma of mitral cells were in contact with boutons with two types of synaptic vesicles, that is, round and flat vesicles, especially flat vesicles in boutons were showing reciprocal synapses. However, in domestic fowls, vipers, frogs and crussian carps, there were found boutons showing only spherical synaptic vesicles. 6. The boutons containing round synaptic vesicles were made contact with the some of tufted cell of olfactory bulb in the rabbits, fowls, vipers and frogs, but no synaptic boutons were observed in soma of tufted cells in crussian carps. In the frogs, there were observed dendrites were contact with the soma of tufted cells. 7. In the neuropils of plexiform, granular and glomerular layers olfactory bulbs in the vertebrate, the synapses were axo-large dendrites, axo-median and small dendrites, dendrodendritic, and axo-axonal contacts. However, in the neuropil of crussian carps, synapses were observed only in glomerular layer.

• Journal of Sensor Science and Technology
• /
• v.6 no.4
• /
• pp.328-336
• /
• 1997

The CdSe thin films were grown on the Si(100) wafers by a hot wall epitaxy method (HWE). The source and substrate temperature are $600^{\circ}C$ and $430^{\circ}C$ respectively. The crystalline structure of epilayers was investigated by double crystal X-ray diffraction(DCXD). Hall effect on the sample was measured by the van der Pauw method and studied on the carrier density and mobility dependence on temperature. From Hall data, the mobility was increased in the temperature range 30K to 150K by impurity scattering and decreased in the temperature range 150k to 293k by the lattice scattering. In order to explore the applicability as a photoconductive cell, we measured the sensitivity(${\gamma}$), the ratio of photocurrent to darkcurrent(pc/dc), maximum allowable power dissipation(MAPD), spectral response and response time. The results indicated that the photoconductive characteristic were the best for the samples annealed in Cu vapor compare with in Cd, Se, air and vacuum vapour. Then we obtained the sensitivity of 0.99, the value of pc/dc of $1.39{\times}10^{7}$, the MAPD of 335mW, and the rise and decay time of 10ms and 9.5ms, respectively.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.32 no.6
• /
• pp.882-889
• /
• 2008

Three fabrics, 100% silk, nylon and cotton each, were dyed with a lichen dye solution prepared by a fermentation method under conditions of varying dyebath pH and temperature. To verify the effect of chitosan on fabric dyeing, the 100% cotton fabric was treated with a chitosan solution before dyeing. The K/S, CIE $L^*$, $a^*$, $b^*$, ${\Delta}E$ and Munsell values of the dyed samples were measured. Colorfastness of each sample was also investigated. The maximum K/S value was measured at 520nm wavelength for the dyed silk fabric and at 480nm for the dyed cotton and nylon. The K/S values for the dyed silk fabric were much greater than those of the other fabrics. The dyed silk fabric showed a red tone on the Munsell color system, and the dyed nylon and cotton fabrics a yellowish red tone. Dye affinity to fabrics was better in a neutral or acidic dyebath. As dyeing temperature increased, K/S values increased for the dyed nylon and cotton fabrics but not for the silk. Dyeability of cotton fabrics could improve by Chitosan treatment. As for most natural dyes, colorfastness of all dyed samples was poor. The silk fabric showed an excellent dry cleaning fastness of Grade 5.

• Journal of Dairy Science and Biotechnology
• /
• v.32 no.2
• /
• pp.111-119
• /
• 2014

This study was carried out to investigate the quality characteristics and antioxidant activity of a functional drink prepared by mixed fermentation of oak mushroom extract and whey. As the ratio of oak mushroom extract increased, the pH value of the whey fermentative solution decreased proportionally, and the titratable acidity increased significantly. The number of lactic acid bacteria after 24 hours of culture was at a level of $10^{11}CFU/mL$ in all whey fermentative solutions containing oak mushroom extracts. DPPH and ABTS radical scavenging activities after 24 hours of culture were higher in a fermentative solution containing oak mushroom extract than in the control. After 24 hours of culture, the nitric oxide production in whey fermentation solution by LPS-induced RAW 264.7 cells was lower compared to that in whey fermentation solution with oak mushroom. Sensory evaluation revealed that, color, flavor, taste, and overall acceptability of the whey fermentation solution sample, which contained 1.0% oak mushroom extract, were much better than those of the other groups. Sensory evaluation of a whey drink containing oak mushroom flavor indicated that the whey drink containing 0.001% oak mushroom flavor was better than the other samples.

• Korean Journal of Environmental Agriculture
• /
• v.34 no.3
• /
• pp.161-167
• /
• 2015

BACKGROUND: For the heavy metal cotamination sites, it is very important to estimate the human bioavailability quotients for heavy metals in paddy soils released from mine tailings, which is a major source of contamination in Korea, and to assess the human health risks of heavy metals. METHODS AND RESULTS: This experiment was carried out to investigate the human bioavailability quotient of the heavy metals in paddy soils below part of the closed metalliferous mine. For estimating the human bioavailability quotients for heavy metals, 30 paddy soils below part of the closed mine were collected, and analyzed for Cd, Cu, Pb, Zn, and As using simple bioavailability extraction test(SBET). The quantities of Cd, Cu, Pb, Zn and As extracted from paddy soils below part of the mine by using the SBET analysis were 28.1, 17.3, 34.1, 14.6 and 2.3% respectively. Specially, the maximum values of Cd, Pb and Zn were 73.3, 81.5 and 58.1% of human bioavailability quotient, respectively, and varied considerably among the sampling sites. The human bioavailability quotient of Cd, Cu, Pb and Zn in soils near the closed mine showed significant positive correlation among soil pH value, O.M. and Ex. Ca. contents, while it correlated negatively between soil Ex. K and Ex. Mg contents in paddy soils. Also, its of Cd, Cu, Pb and Zn in paddy soils showed significant positive correlation with 0.1M HCl extractable and total contents, while in soils, it correlated negatively with As content in soil near the closed mine. CONCLUSION: The results of the simple bioavailability extraction test (SBET) indicate that regular ingestion of soils by the local population could be closed a potential health threat due to long-term heavy metals exposure in these mine areas.

• Analytical Science and Technology
• /
• v.29 no.4
• /
• pp.170-178
• /
• 2016

Accuracy and precision of ID methods for different spike isotopes of ⁷⁶Se, ⁷⁷Se, and ⁷⁸Se were compared for the analysis of Selenium using quadrupole ICP/MS equipped with Octopole reaction cell. From the analysis of Se inorganic standard solution, all of three spikes showed less than 1 % error and 1 % RSD for both short-term (a day) and long-term (several months) periods. They showed similar results with each other and ⁷⁸Se showed was a bit better than ⁷⁶Se and ⁷⁷Se. However, different spikes showed different results when NIST SRM 1568a and SRM 2967 were analyzed because of the several interferences on the m/z measured and calculated. Interferences due to the generation of SeH from ORC was considered as well as As and Br in matrix. The results showed similar accuracy and precisions against SRM 1568a, which has a simple background matrix, for all three spikes and the recovery rate was about 80% with steadiness. The %RSD was a bit higher than inorganic standard (1.8 %, 8.6 %, and 6.3 % for ⁷⁸Se, ⁷⁶Se and ⁷⁷Se, respectively) but low enough to conclude that this experiment is reliable. However, mussel tissue has a complex matrix showed inaccurate results in case of ⁷⁸Se isotope spike (over 100 % RSD). ⁷⁶Se and ⁷⁷Se showd relatively good results of around 98.6 % and 104.2 % recovery rate. The errors were less than 5 % but the precision was a bit higher value of 15 % RSD. This clearly shows that Br interferences are so large that a simple mathematical calibration is not enough for a complex-matrixed sample. In conclusion, all three spikes show similar results when matrix is simple. However, ⁷⁸Se should be avoided when large amount of Br exists in matrix. Either ⁷⁶Se or ⁷⁷Se would provide accurate results.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.4
• /
• pp.465-471
• /
• 2008

Physicochemical characteristics of black garlic were analyzed. Colorimetry measurement showed that the black garlic, compared with fresh and steamed garlics, was the highest in a value and the lowest in L and b values. Crude lipid, crude protein, and total sugars were the highest in black garlic, which was followed by steamed and fresh garlic. On the other hand, moisture content was the lowest in the black garlic and the highest in the fresh garlic. The pH of garlics was ca. 6.8, 6.5, and 4.4 in fresh, steamed, and black garlic, respectively, which indicated that garlics tended to be acidified with the thermal processing. Total pyruvate and total thiosulfinates were the lowest in steamed garlic ($77{\mu}mol$/g and 0.07 OD/g for each) and the highest in black garlic ($278{\mu}mol$/g and 0.77 OD/g). Arabinose and galactose were detected only in black garlic and their contents were 1.6 and 13 mg/100 g, respectively. Free sugars such as glucose, sucrose and fructose were the highest in the order of fresh, steamed, and black garlic. Potassium was a predominant mineral in all garlics, constituting 76% of total minerals. Glutamic acid, arginine, and aspartic acid were the major composition amino acids in all garlics, regardless of processing conditions. 15 kinds of free amino acids were detected in fresh and steamed garlic, while five more free amino acids, O-phosphoethanolamine, and urea were additionally detected in black garlic.

• Korean Journal of Poultry Science
• /
• v.43 no.2
• /
• pp.77-88
• /
• 2016

To establish a new synthetic Korean meat chicken breed, we tested $5{\times}5$ diallel cross mating experiment with domestic chicken breeds. Comparing stress responses among diallel crossed chicken breeds, we analyzed telomere length, DNA damage and expressions of heat shock protein genes (HSPs) as the markers of the stress response. The telomere length was measured by quantitative fluorescence in situ hybridization on the nuclei of lymphocytes. The expression levels of HSP-70, $HSP-90{\alpha}$ and $HSP-90{\beta}$ genes were analyzed by quantitative real-time polymerase chain reaction in lymphocytes. The DNA damage rate of lymphocytes was quantified by the comet assay known as the single cell gel electrophoresis. In results, there were significant differences in the values of the stress markers such as telomere length, HSPs and DNA damage rate, and also were significant differences in viabilities and body weights among the $5{\times}5$ diallel crossed chicken breeds. The telomere shortening rate, expression values of HSPs and DNA damage rate were significant low in W and Y crossed chickens compare to the others, but GG pure breed showed the highest values in the 25 crossed chickens. Estimating correlation coefficient, the survival rate positively correlated to telomere length, but negatively correlated to the expression levels of HSP-70, $HSP-90{\alpha}$, $HSP-90{\beta}$ genes and to the value of % DNA in tail as DNA damage rate. The expression levels of HSP-70, $HSP-90{\alpha}$ and $HSP-90{\beta}$ genes of dead chickens had significantly higher than those of survival chickens. According to the results on the stress marker analysis, it would be considered that the crossed breeds had more stress resistant than the pure breeds, and the crossed chickens with a light strain such as W or Y were relatively resistant to stress, but the crossed chickens with a heavy strain such as G, H, F were susceptible to stress.

• Korean Journal of Soil Science and Fertilizer
• /
• v.21 no.3
• /
• pp.264-271
• /
• 1988

This experiment was carried out to investigate the effects of long-term applications of organic matters on the chemical properties and on the application levels of nitrogen in Fluvio-Alluvial plain of Jeonbug series. The amounts of application of rice straw and compost, the sources of organic matters, were 500 and 1,000 kg/10a in combined with the different nitrogen levels of 0.15 and 20 kg/10a, respectively. The results obtained from the 9 year's experiment during 1979 to 1987 were summarized as follows: I. In long-term application of Organic matter the soil pH showed the lowest value in the 3rd-4th year at rice straw and 5th-6th year at compost but it varied less in control plot for 9 years. 2. Organic matter content in the soils was gradually increased by yearly application of organic matter, while it was higher in rice straw than in compost since the 5th year. 3. The contents of available silica and available phosphate in soil were rapidly increased by long-term application of organic matter and it was especially higher in rice straw than compost, but it was gradually decreased in control plot. 4. The contents of exchangable cations (Ca, Mg and K) and the total nitrogen were increased by long-term application of organic matter they were in rice straw than in compost. But they showed decreasing tendency in control plot. 5. The soil Eh was lower in order of rice straw, compost and control plot however application of orgnic matter resulted in increasing soil Eh due to the rapid reduction of soil from panicle formation to heading stage in rice cultivation. 6. The number of panicles per $m^2$ and the number of granis per panicle were increased by increment of nitrogen levels in all treatments and especially largest in rice straw application. But 1,000 grain weight increased in low nitrogen level with long-term applications of organic matter. 7. It was estimated that the application levels of nitrogen by long-term application of organic matter were 21, 24 and 20 kg/10a for 1st-3rd, 4th-6th and 7th-9th year in rice straw application, and 16 and 19 kg/10a for 1st-3rd and 4th-9th year in compost application, respectively.